26 May 2014

NASA unveils new home for space rats

Attention space rats and astromice, NASA is sending new, posher rodent habitats to the International Space Station (ISS). The high-tech cages will first will fly in August aboard an unmanned SpaceX Dragon cargo ship and are part of an extensive study on the effects of weightlessness on prolonged space voyages.

Rodents have been part of the US space program since the first mice flew in a V-2 rocket in 1950. Though the chimps and monkeys may have taken the spotlight, mice and rats have played a vital role in space medicine with no less than 27 batches of rodents flying on the Space Shuttle from 1983 to 2011. However, the new round of rodent studies on the ISS mean that there’s a need for something more sophisticated than a shoebox to carry the animals around in.

Developed at NASA’s Ames Research Center in Moffett Field, California, the new habitats are designed for transporting the animals to the space station and as part of their long-term accommodation. They consist of a transport module, which fits inside the racks in the pressurized cargo section of the Dragon spacecraft, and an access module for moving the rodents from the transporter to the station’s rodent habitat without having the mice escape and take up residence behind the control panels. The access modules also allow the crew to remove than animals from the habitat for observation.

The habitat modules hold 10 mice or 6 rats and are designed to provide them with water, food, lighting and fresh air. Since rats and mice aren't made for flight, the habitat is also equipped with rods for them to grasp as they move about. The habitats are also bugged with data links and a visual/infrared video system, so scientists can keep a constant eye on their charges.

Based on recommendations of the National Research Council, the new modules are part of a study of the effects of prolonged weightlessness, such as would be encountered on a mission to Mars. The six-month tours of duty that astronauts spend on the ISS have revealed a number of problems with living in zero-G, including loss of muscle mass, weakening of bones, as well as affecting the cardiovascular endocrine, nervous, reproductive, and immune systems. A two-year Mars mission could have severe, or perhaps fatal effects especially when space radiation is included. The research is aimed at understanding these effects at the genetic and molecular level in hopes of finding ways to combat them. NASA also says that some of these conditions resemble some earthbound diseases and could help in their treatment.

For such a study, rodents provide many advantages. For one thing, their organs, diet, immune system, and genome are very similar to humans in many respects. Also, as any mourning 10-year old can tell you, they age very quickly compared to humans. With a lifespan of only 18 months to two years, a rodent can experience weightless effects that would take many years in a person, so a six-month visit to the space station by a rat can give great insights into how long space voyages will affect the crews. In addition to this, it’s possible to study rats at all stages of their development something that’s impossible in astronaut crews aged between their late 20s to early 50s. Also, different breeds of rodents can be used for cross referencing.

“Studies that use different genetic strains of rodents will help researchers pinpoint the roles played by specific genes in gravity sensing and responses,” says Ruth Globus, Ph.D., Rodent Research Project scientist and researcher in the Space Biosciences Division at Ames.

The first flight of the new rodent residence is scheduled for SpaceX’s CRS-4 mission in August 8, after which the modules will undergo a technical assessment and be used in studies focusing on muscle atrophy and treatment. If all goes well, a second rodent mission will fly on CRS-6.